In a heavy saucepan, heat the pumpkin seeds and sunflower seeds. Heat until the pumpkin seeds sizzle and pop. Do not use oil, just heat on medium high heat until roasted. Set aside to cool.
In the bowl of a food processor, add the oregano and garlic. Drizzle olive oil in until a puree forms.
Slowly add cooled roasted seeds. Puree.
Refrigerate unused portions for up to a week. You can also freeze; just be aware that the olive oil clumps in the freezer and needs to defrost and be stirred back into the recipe.